This invention relates to a process for producing solid aluminum chloride compositions.
Solutions of aluminum salts such as, for example, aluminum sulfate or basic aluminum salts, are used extensively as water treating agents for purification and treatment of waste water, ground water, etc. Among the basic aluminum salts, basic aluminum chloride salt solutions exhibit a good water clarifying effect throughout broad pH and temperature ranges.
The production of stable solutions of basic sulfate containing aluminum chloride compositions is described, for example, in West German Offenlegungschrift No. DE-OS No. 24 18 416. In this publication a whole series of prior known processes for producing solutions of basic aluminum salts are described, but all of them are very expensive or produce products with unsatisfactory characteristics. The product of the process of DE OS No. 24 18 416, itself produces satisfactory results in water treatment, but the process for its production is, however, also very expensive.
In addition, it would be desirable to produce a solid substance in order to avoid problems which arise in formulating and transporting solutions. Attempts to obtain a solid material by evaporation of the solvent from a solution which had been produced according to DE-OS No. 24 18 416, led only to a product with inferior clarifying effectiveness.